Protective container



July 7, 1970 BAMBARA ET AL 3,519,189

PROTECTIVE CONTAINER Filed July 10, 1968 3 Sheots-SIwet 1 INVENTORS:

HOWARD A. ROHDIN JOHN D. BAMBARA AT nmzvs y 7, 1970 J. D. BAMBARA ET AL3,519,189

PROTECTIVE CONTAINER Filed July 10', 1968 5 sheets-smat- INVENTORS:

HOWARD A. ROHDIN JOHN D. BAMBARA ATTORN EYS Jfily 7, 1970 J. D B M RETAL 3,519,189

PROTECTIVE CONTAINER 3 Sheets-Sheet :5

Filed July 10, 1968 FIG. 6.

INVENTORS:

HOWARD A. ROHDIN JOHN D. BAMBARA United States Patent US. Cl. 229--2.5 6Claims ABSTRACT OF THE DISCLOSURE There is disclosed an egg carton madeof a material such as foamed polystyrene in which at least onelongitudinal edge, where the top and bottom of the carton come together,has spaced identations and a heat sealed joining of the top and bottomportions at these identations. In one embodiment, the secondlongitudinal edge where the top and bottom portions come together hasrelatively short spaced hinges so that when the carton is open, the topportion can either be refolded back or can be torn off, at option of theuser. In addition, each of these hinges has a length sufliciently smallso that they can readily be melted through and a heat seal effected.When a heat seal is effected at various spots along both longitudinaledges of the carton, the top of the carton can easily be torn off by theuser.

This invention relates in general to a protective container and moreparticularly to an improved means for sealing together the top andbottom portions of an egg carton.

BACKGROUND OF THE INVENTION Foamed polystyrene egg cartons have become amajor component of the egg carton industry. Each carton is separatelystamped from a sheet of foamed polystyrene and the stamping process isone wherein the bottom and top portions of the egg carton are stamped asa single unit with a longitudinal hinge permitting the top portion to beswung over on top of the bottom portion after the bottom portion hasbeen filled with eggs. Typically, the bottom portion has a seven-eighthsto one inch flap, into which flap latching means such as protrusions areformed during the thermo-forming process. Where the latching means areprotrusions, they mate with openings in the side wall of the top portionso that the egg carton will be held closed.

This particular design has the disadvantage that the carton may bereadily opened in the store, the eggs handled, broken and stolen. It hasa further disadvantage that the hold is not sufficiently positive toguarantee that the top portions will not pop open. Accordingly, it hasbeen known to use the expedient of adding a lateral tape closure whichhas the disadvantage of being time consuming and unsightly. Becausethese egg cartons have to be sold for two to three cents a piece, theadditional step of taping the edges adds a significant cost factor.

Accordingly, it is a major purpose of this invention to provide a meansfor closing the egg carton which will be a permanent closure, until theegg carton is opened by the ultimate consumer, and yet will not involveadditional relatively expensive steps or material.

It is a related purpose of this invention to provide such a permanentclosure as can readily be broken by the ultimate user without damage tothe eggs.

One of the major elements in the cost of the egg carton is the cost ofthe sheets of foam polystyrene which are thermoformed into the ultimateegg carton by means of matching male and female dies. The cost of theegg carton and of the foamed polystyrene material is by no means icenegligible when compared with the cost of the dozen eggs which go intoeach carton. Accordingly, any savings in the amount of polystyrenematerial necessary will have a meaningful impact on the total cost ofthe end product.

Thus it is another major purpose of this invention to reduce the amountof foamed polystyrene material needed in forming the egg carton.

*It is a more specific and related purpose of this invention toeliminate the need for the seven-eighths to one inch wide flap which isused to join the top and bottom portions of the carton. But, it is animportant purpose of this invention to eliminate the need for this flapwithout requiring additional foamed polystyrene or other additionalmaterial which would simply replace the cost of the material saved.

BRIEF DESCRIPTION OF THE INVENTION In brief, one embodiment of thisinvention involves a foamed polystyrene egg carton formed by the usualtechniques of thermo-forming in which the top portion is formed hingedto the bottom portion. However, the hinges formed are relatively shortin length, being approximately one-fourth inch in length, and are aplurality in number, spaced from one another along one of thelongitudinal edges joining the top and bottom portions. Longitudinally,these hinges are preferably positioned between the pockets containingeggs so that a heat carrying member can be brought into contact with thehinges to cause the hinges to melt and form a heat seal at each of thesepoints. The other longitudinal edge, wherein the top and bottom portionsof the egg carton are joined, has a plurality of spaced heat seals. Eachof these heat seals are preferably located between adjacent egg pocketswhere top and bottom portions of the container are recessed inwardlythereby facilitating placing a heat carrying member at the edges so asto seal the edges at the points desired.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects and purposes of thisinvention will become apparent from the following detailed descriptionand drawings, in which:

FIG. 1 is a perspective view of the carton of this invention in whichthe top and bottom portions are open and the interior of the egg cartonis shown and the individual hinges that permit the top portion to berefolded on the bottom portion are shown along the edge joining the topand bottom portions;

FIG. 2 is a perspective view of the FIG. 1 carton, in which top andbottom portions are closed, showing the heat seal on one edge and hingeon the other;

FIG. 3 is a perspective view of the FIG. 1 carton with the top andbottom portions closed and sealed together, showing heat seals on bothedges;

FIG. 4 is a cross sectional view along the plane 4-4 in FIG. 2 showing aseal on one edge and a hinge on the other in cross section;

FIG. 5 is a perspective view of an embodiment wherein a separatefastener is used to effect closure;

FIG. 6 is a cross section along the plane 6-6 of FIG. 5;

FIG. 7 is a perspective veiw of one of the fasteners that may be used inthe FIG. 5 embodiment; and

FIG. 8 is a perspective view of an embodiment wherein spot heat sealsare used to effect closure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to the drawings,FIGS. 1 through 4 views of the same egg carton 10, illustrating the eggcarton in both opened (FIG. 1) and closed, sealed (FIGS. 2 and 3) state.

As may be seen from the figures, the carton has a top portion 12 and abottom portion 14. The bottom portion 14 has a series of shaped eggholding cells 16 of known design for holding each egg (no eggs areshown) individually so that the eggs do not rattle against one another.Various means may be provided, if desired, in the top cover to fit,secure or relegate each egg.

In the embodiment shown, there are five separate, spaced from oneanother, hinges 20 joining the top portion 12 and bottom portion 14 ofthe egg carton 10. For two reasons, the length of each hinge 20 ispreferably small, in the order of magnitude of one-quarter of an inch.

First, the relatively small in length hinge 20 makes it much easier forthe ultimate consumer to readily tear off the top portion 12 whenopening the egg carton. The bottom portion may be used to store the eggsand permit easy access. As far as this feature is concerned, the factthat the hinges 20 are provided gives the ultimate consumer the optionof tearing off the top portion 12 or continuing to retain the topportion and employing the hinges 20 to refold the top portion back ontop of the bottom portion 14.

A second reason for having the hinges 20 relatively short in length isto make it a relatively simple step to place a heating implement on thehinges, after packing eggs in the carton and after folding the topportion 12 over the bottom portion 14, so as to effect a heat seal ateach hinge position. When such is done, the hinges are destroyed becausethey are melted away and replaced by a heat seal along the edge betweenthe top and bottom portions of the egg carton. In the embodiment wherethe manufacturer thereby replaces the hinge 20 with the heat seal, theultimate consumer has to destroy the seal in order to gain access to theeggs.

FIG. 3 best shows the plurality of edge seals 22 which, when foamedpolystyrene is employed, are formed by the simple application of localheat. These edge seals 22 are formed alOng at least one of thelongitudinal lines joining the top portion 12 and bottom portion 14 ofthe carton. In one form of the invention, the second edge may have thehinges shown in FIGS. 1 and 2 or, alternatively, may have a second rowof edge seals 22 as shown in FIG. 3.

As may be seen from FIGS. 2 and 3, the top portion 12 is formed withindentations 24 along its outer surface adjacent to the area where theedge seals 22 are formed. These indentations 24 permit a heat carryingtool to be brought into contact with the edges of the rim 26 of thecarton to form the heat seal while avoiding contact with the rest of thesurface of the top portion. Such contact with the top portion 12 isundesirable since it would melt and distort the shape of the top portionand produce both unsightly and unpredictable results. For the samereason, the edge seals 22 are preferably located between the cells 16 inthe bottom portion 14. When so located, the natural indentations betweencells 16 afford protection from the heat carrying tool which effects theedge seals 22.

In forming the edge seals 22, the top portion 12 is folded over thebottom portion 14 in the normal fashion. Heat carrying rods are broughtinto contact with the rim 26 along the edges of the carton where it isdesired to form the edge seals 22. At the same time, the flanged out rimportions 26 of the top 12 and of the bottom 14 are held in contactagainst one another when the heat carrying member is applied. Thisassures that the portion of the rims 26 which are to form the edge seals22 will fuse with one another and not be separated by a gap.

It should be noted in connection with the above described embodimentthat the combination of edge seals 22 and hinges 20 provides an eggcarton (see FIG. 2) which is permanently sealed until the ultimateconsumer opens it and which affords the ultimate consumer the option ofeither retaining or discarding the top portion 12.

In addition, the egg carton illustrated in FIG. 1, with one row ofhinges, provides a universal intermediate product which can be used bythe egg processor to provide either one of two types of egg cartons forthe ultimate consumer. The first type of egg carton is, as justdescribed, one with the hinges 20 along one longitudinal edge and theedge seals 22 along the other longitudinal edge. The second type of eggcarton is one with edge seals 22 along both longitudinal edges, thehinges having been melted and replaced by edge seals.

Furthermore, this edge seal technique completely eliminates the need fora closing flap and thus saves on material. In addition, by eliminatingthe need for a latching means to effect closure, this inventionsimplifies the manufacture of the egg carton. For example, in one of thepresently used types of cartons, holes must be punched in the topportion to mate with the knobs in the flap hinges to the bottom portion.This invention eliminates the need to punch such holes.

It should also be noted that achieving the objects of this invention bythe technique described enables continued use of egg cartons having theover all shape and configuration required by presently employed eggcarton filling and handling machinery. Thus the advantages of thisinvention are achieved with the further advantage of being able to usepresently installed equipment. All that will be required in the way ofadditional equipment is relatively minor peripheral equipment such as toapply the heat to the edges of the closed carton in order to form theedge seals 22.

Thus it can be seen that the various seemingly confiicting purposes ofthis invention to achieve a permanent edge seal without requiringadditional egg carton mate rial (and, indeed, while saving on egg cartonmaterial) and yet enabling the continued use of presently employed eggcarton handling and loading machinery are all achieved. The particulartechnique of this invention is simple but therein lies its value in thatit achieves a number of purposes without increasing the cost of an itemwhich must be kept relatively low in cost in order for it to be afeasible packaging device for eggs.

FIGS. 5 through 7 illustrate a further embodiment wherein the basic FIG.1 embodiment is sealed by means of separate fasteners 30. Thesefasteners 30, which may be made of either metal or plastic, provide theoption for a user of a readily reclosable carton 10. As may be seen inFIG. 5, the hniges 20 are left in place, without being heat sealed away,so that the top 12 can be readily opened and closed when the fasteners30 are removed. The fasteners 30 extend through the rim 26 at thepositions where the indentations 24 are located. Because the design ofthis carton 10 includes the indentations 24, enough space is providedalong the rim 26, at the indentations 24, so that fasteners, such as thefasteners 30, may be employed. In this fashion, a removable fastener isprovided and the user can, after removing the fasteners 30, open andclose the container 10. However, the design makes it possible to achievethis function without requiring additional closure flaps or extended rim26 areas. Thus the FIG. 5 embodiment meets a major objective of thisinvention, which is to save on the cost of material required for thecarton 10 involved.

FIG. 8 illustrates a further embodiment wherein spot heat seals 32 areused to effect closure. Because this carton design includes theindentations 24, there is space at the indentations to spot heat sealwithout melting or distorting other portions of the carton. Thus theFIG. 8 embodiment, like the FIG. 5 embodiment, meets a major objectiveof this invention, which is to eliminate the need for additionalmaterial to form flaps to provide a closure.

Although various embodiments of this invention have been described indetail, it should be obvious that certain aspects of the embodimentsdescribed may be varied without departing from the scope of thisinvention.

For example, the invention has been described in an egg containerembodiment. Yet the container design could be made for light bulbs,Christmas tree ornaments, fruits or the like.

The invention has been described in connection with a specificembodiment including foamed polystyrene since such material has beenfound useful in the practice of this invention. However, it should beunderstood that other material, which can be similarly formed intocartons and in particular materials which can be thermoformed, may beemployed. Thus, other foamed plastic materials could be employed toprovide the embodiments illustrated in the various figures.

What is claimed is:

1. In a carton having a top portion and a bottom portion, said bottomportion having a plurality of cells for retaining articles therein andindentations in a pair of opposite outer walls corresponding to thespaces between adjacent cells, and said top portion having correspondingindentations in at least one of a like pair of opposite outer walls,whereby with said carton in closed position, the indentations on saidtop and bottom portions are in registry; the improvement comprising,

a plurality of spaced hinge means integrally joining said top and bottomportions along the associated edges of a first pair of correspondingouter walls thereof, each of said hinge means being positioned adjacentthe indentations in said first pair of outer walls,

and means along the edges of a second pair of corresponding outer wallsof said top and bottom portions opposite said first named pair adaptedto receive fastening means to retain said carton-portions in closedposition, said fastening receiving means being positioned adjacent apair of aligned indentations in said second pair of outer walls.

2. The carton of claim 1 wherein said top and bottom portions and saidhinge means are integrally formed of a foamed plastic material.

3. The carton of claim 1 wherein each of said top and bottom portionsinclude flange portions forming the bases of the indentations in theouter walls thereof with the corresponding flange portions of each pairof aligned indentations coming into contact upon closure of the cartonto provide said fastening receiving means.

4. The carton of claim 3 wherein said fastening means comprises a spotheat seal joining said contacting flange means of at least one pair ofsaid indentations.

5. The carton of claim 3 wherein said fastening means eomprises aseparate mechanical fastener joining said contacting flange means of atleast one pair of said indentations.

6. The carton of claim 3 wherein each of said hinge means is ofrelatively short length to permit ready separation of said top andbottom portions.

References Cited UNITED STATES PATENTS 2,162,162 6/1939 Murguiondo229-2.5 X 3,326,443 6/1967 Burkett 229-2.5 3,333,760 8/1967 Bridenstine2292.5 X 3,424,363 1/1969 Donovan 2292.5

DAVID M. BOCKENEK, Primary Examiner U.S. Cl. X.R. 229--44, 45

